wp-includes/pomo/translations.php

   1 <?php
   2 /**
   3  * Class for a set of entries for translation and their associated headers
   4  *
   5  * @version $Id: translations.php 1157 2015-11-20 04:30:11Z dd32 $
   6  * @package pomo
   7  * @subpackage translations
   8  */
   9
  10 require_once dirname(__FILE__) . '/entry.php';
  11
  12 if ( ! class_exists( 'Translations', false ) ):
  13 class Translations {
  14         var $entries = array();
  15         var $headers = array();
  16
  17         /**
  18          * Add entry to the PO structure
  19          *
  20          * @param array|Translation_Entry &$entry
  21          * @return bool true on success, false if the entry doesn't have a key
  22          */
  23         function add_entry($entry) {
  24                 if (is_array($entry)) {
  25                         $entry = new Translation_Entry($entry);
  26                 }
  27                 $key = $entry->key();
  28                 if (false === $key) return false;
  29                 $this->entries[$key] = &$entry;
  30                 return true;
  31         }
  32
  33         /**
  34          * @param array|Translation_Entry $entry
  35          * @return bool
  36          */
  37         function add_entry_or_merge($entry) {
  38                 if (is_array($entry)) {
  39                         $entry = new Translation_Entry($entry);
  40                 }
  41                 $key = $entry->key();
  42                 if (false === $key) return false;
  43                 if (isset($this->entries[$key]))
  44                         $this->entries[$key]->merge_with($entry);
  45                 else
  46                         $this->entries[$key] = &$entry;
  47                 return true;
  48         }
  49
  50         /**
  51          * Sets $header PO header to $value
  52          *
  53          * If the header already exists, it will be overwritten
  54          *
  55          * TODO: this should be out of this class, it is gettext specific
  56          *
  57          * @param string $header header name, without trailing :
  58          * @param string $value header value, without trailing \n
  59          */
  60         function set_header($header, $value) {
  61                 $this->headers[$header] = $value;
  62         }
  63
  64         /**
  65          * @param array $headers
  66          */
  67         function set_headers($headers) {
  68                 foreach($headers as $header => $value) {
  69                         $this->set_header($header, $value);
  70                 }
  71         }
  72
  73         /**
  74          * @param string $header
  75          */
  76         function get_header($header) {
  77                 return isset($this->headers[$header])? $this->headers[$header] : false;
  78         }
  79
  80         /**
  81          * @param Translation_Entry $entry
  82          */
  83         function translate_entry(&$entry) {
  84                 $key = $entry->key();
  85                 return isset($this->entries[$key])? $this->entries[$key] : false;
  86         }
  87
  88         /**
  89          * @param string $singular
  90          * @param string $context
  91          * @return string
  92          */
  93         function translate($singular, $context=null) {
  94                 $entry = new Translation_Entry(array('singular' => $singular, 'context' => $context));
  95                 $translated = $this->translate_entry($entry);
  96                 return ($translated && !empty($translated->translations))? $translated->translations[0] : $singular;
  97         }
  98
  99         /**
 100          * Given the number of items, returns the 0-based index of the plural form to use
 101          *
 102          * Here, in the base Translations class, the common logic for English is implemented:
 103          *      0 if there is one element, 1 otherwise
 104          *
 105          * This function should be overridden by the sub-classes. For example MO/PO can derive the logic
 106          * from their headers.
 107          *
 108          * @param integer $count number of items
 109          */
 110         function select_plural_form($count) {
 111                 return 1 == $count? 0 : 1;
 112         }
 113
 114         /**
 115          * @return int
 116          */
 117         function get_plural_forms_count() {
 118                 return 2;
 119         }
 120
 121         /**
 122          * @param string $singular
 123          * @param string $plural
 124          * @param int    $count
 125          * @param string $context
 126          */
 127         function translate_plural($singular, $plural, $count, $context = null) {
 128                 $entry = new Translation_Entry(array('singular' => $singular, 'plural' => $plural, 'context' => $context));
 129                 $translated = $this->translate_entry($entry);
 130                 $index = $this->select_plural_form($count);
 131                 $total_plural_forms = $this->get_plural_forms_count();
 132                 if ($translated && 0 <= $index && $index < $total_plural_forms &&
 133                                 is_array($translated->translations) &&
 134                                 isset($translated->translations[$index]))
 135                         return $translated->translations[$index];
 136                 else
 137                         return 1 == $count? $singular : $plural;
 138         }
 139
 140         /**
 141          * Merge $other in the current object.
 142          *
 143          * @param Object &$other Another Translation object, whose translations will be merged in this one
 144          * @return void
 145          **/
 146         function merge_with(&$other) {
 147                 foreach( $other->entries as $entry ) {
 148                         $this->entries[$entry->key()] = $entry;
 149                 }
 150         }
 151
 152         /**
 153          * @param object $other
 154          */
 155         function merge_originals_with(&$other) {
 156                 foreach( $other->entries as $entry ) {
 157                         if ( !isset( $this->entries[$entry->key()] ) )
 158                                 $this->entries[$entry->key()] = $entry;
 159                         else
 160                                 $this->entries[$entry->key()]->merge_with($entry);
 161                 }
 162         }
 163 }
 164
 165 class Gettext_Translations extends Translations {
 166         /**
 167          * The gettext implementation of select_plural_form.
 168          *
 169          * It lives in this class, because there are more than one descendand, which will use it and
 170          * they can't share it effectively.
 171          *
 172          * @param int $count
 173          */
 174         function gettext_select_plural_form($count) {
 175                 if (!isset($this->_gettext_select_plural_form) || is_null($this->_gettext_select_plural_form)) {
 176                         list( $nplurals, $expression ) = $this->nplurals_and_expression_from_header($this->get_header('Plural-Forms'));
 177                         $this->_nplurals = $nplurals;
 178                         $this->_gettext_select_plural_form = $this->make_plural_form_function($nplurals, $expression);
 179                 }
 180                 return call_user_func($this->_gettext_select_plural_form, $count);
 181         }
 182
 183         /**
 184          * @param string $header
 185          * @return array
 186          */
 187         function nplurals_and_expression_from_header($header) {
 188                 if (preg_match('/^\s*nplurals\s*=\s*(\d+)\s*;\s+plural\s*=\s*(.+)$/', $header, $matches)) {
 189                         $nplurals = (int)$matches[1];
 190                         $expression = trim($this->parenthesize_plural_exression($matches[2]));
 191                         return array($nplurals, $expression);
 192                 } else {
 193                         return array(2, 'n != 1');
 194                 }
 195         }
 196
 197         /**
 198          * Makes a function, which will return the right translation index, according to the
 199          * plural forms header
 200          * @param int    $nplurals
 201          * @param string $expression
 202          */
 203         function make_plural_form_function($nplurals, $expression) {
 204                 $expression = str_replace('n', '$n', $expression);
 205                 $func_body = "
 206                         \$index = (int)($expression);
 207                         return (\$index < $nplurals)? \$index : $nplurals - 1;";
 208                 return create_function('$n', $func_body);
 209         }
 210
 211         /**
 212          * Adds parentheses to the inner parts of ternary operators in
 213          * plural expressions, because PHP evaluates ternary oerators from left to right
 214          *
 215          * @param string $expression the expression without parentheses
 216          * @return string the expression with parentheses added
 217          */
 218         function parenthesize_plural_exression($expression) {
 219                 $expression .= ';';
 220                 $res = '';
 221                 $depth = 0;
 222                 for ($i = 0; $i < strlen($expression); ++$i) {
 223                         $char = $expression[$i];
 224                         switch ($char) {
 225                                 case '?':
 226                                         $res .= ' ? (';
 227                                         $depth++;
 228                                         break;
 229                                 case ':':
 230                                         $res .= ') : (';
 231                                         break;
 232                                 case ';':
 233                                         $res .= str_repeat(')', $depth) . ';';
 234                                         $depth= 0;
 235                                         break;
 236                                 default:
 237                                         $res .= $char;
 238                         }
 239                 }
 240                 return rtrim($res, ';');
 241         }
 242
 243         /**
 244          * @param string $translation
 245          * @return array
 246          */
 247         function make_headers($translation) {
 248                 $headers = array();
 249                 // sometimes \ns are used instead of real new lines
 250                 $translation = str_replace('\n', "\n", $translation);
 251                 $lines = explode("\n", $translation);
 252                 foreach($lines as $line) {
 253                         $parts = explode(':', $line, 2);
 254                         if (!isset($parts[1])) continue;
 255                         $headers[trim($parts[0])] = trim($parts[1]);
 256                 }
 257                 return $headers;
 258         }
 259
 260         /**
 261          * @param string $header
 262          * @param string $value
 263          */
 264         function set_header($header, $value) {
 265                 parent::set_header($header, $value);
 266                 if ('Plural-Forms' == $header) {
 267                         list( $nplurals, $expression ) = $this->nplurals_and_expression_from_header($this->get_header('Plural-Forms'));
 268                         $this->_nplurals = $nplurals;
 269                         $this->_gettext_select_plural_form = $this->make_plural_form_function($nplurals, $expression);
 270                 }
 271         }
 272 }
 273 endif;
 274
 275 if ( ! class_exists( 'NOOP_Translations', false ) ):
 276 /**
 277  * Provides the same interface as Translations, but doesn't do anything
 278  */
 279 class NOOP_Translations {
 280         var $entries = array();
 281         var $headers = array();
 282
 283         function add_entry($entry) {
 284                 return true;
 285         }
 286
 287         /**
 288          *
 289          * @param string $header
 290          * @param string $value
 291          */
 292         function set_header($header, $value) {
 293         }
 294
 295         /**
 296          *
 297          * @param array $headers
 298          */
 299         function set_headers($headers) {
 300         }
 301
 302         /**
 303          * @param string $header
 304          * @return false
 305          */
 306         function get_header($header) {
 307                 return false;
 308         }
 309
 310         /**
 311          * @param Translation_Entry $entry
 312          * @return false
 313          */
 314         function translate_entry(&$entry) {
 315                 return false;
 316         }
 317
 318         /**
 319          * @param string $singular
 320          * @param string $context
 321          */
 322         function translate($singular, $context=null) {
 323                 return $singular;
 324         }
 325
 326         /**
 327          *
 328          * @param int $count
 329          * @return bool
 330          */
 331         function select_plural_form($count) {
 332                 return 1 == $count? 0 : 1;
 333         }
 334
 335         /**
 336          * @return int
 337          */
 338         function get_plural_forms_count() {
 339                 return 2;
 340         }
 341
 342         /**
 343          * @param string $singular
 344          * @param string $plural
 345          * @param int    $count
 346          * @param string $context
 347          */
 348         function translate_plural($singular, $plural, $count, $context = null) {
 349                         return 1 == $count? $singular : $plural;
 350         }
 351
 352         /**
 353          * @param object $other
 354          */
 355         function merge_with(&$other) {
 356         }
 357 }
 358 endif;